1). Field of the Invention
This invention relates to a microelectronic assembly having a thermal interface material for conducting heat from a microelectronic die to a thermally conductive member, and to a method of constructing a microelectronic assembly.
2). Discussion of Related Art
Integrated circuits are usually manufactured in and on semiconductor wafers that are subsequently “diced” or “singulated” into individual dies, each die having a respective integrated circuit. A die is then mounted to a carrier substrate for providing structural integrity to the microelectronic die and for communicating signals, power, and ground to and from the integrated circuit.
Integrated circuits that consume a large amount of power also generate a large amount of heat. A thermally conductive member such as a heat spreader or a heat sink is often attached to the microelectronic die to assist in transfer of heat from the microelectronic die. A thermal interface material having a relatively low melting temperature is also located between the microelectronic die and the thermally conductive member. The thermal interface material is reflowed in an oven and subsequently allowed to cool, to cause proper attachment to the die and the thermally conductive member on opposites sides thereof.
During such a reflow process, the thermally conductive member usually drops by a small distance toward the microelectronic die. Melted portions of the thermal interface material squeeze out from a space between the microelectronic die and the thermally conductive member. Such portions that are squeezed out can reach unintended locations and, for example, create a short circuit.